Penny is a double-entry accounting system. It is inspired
by, but incompatible with, John Wiegley's Ledger, which is available
at http://ledger-cli.org/. Installing this package with cabal
install will install the executable program and the necessary
libraries.

Penny is a double-entry accounting system. It uses traditional
accounting terminology, such as the terms "Debit" and
"Credit". If you need a refresher on the basics of double-entry
accounting, pick up a used accounting textbook from your favorite
bookseller (they can be had cheaply, for less than ten U.S. dollars
including shipping) or check out
http://www.principlesofaccounting.com/, a great free online text.

Penny is based around Penny.Lincoln, a core library to represent
transactions and postings and their components, such as their
amounts and whether they are debits and credits. You can use
Lincoln all by itself even if you don't use the other components
of Penny, which you may find handy if you are a Haskell
programmer. I wrote Penny because I wanted a precise library to
represent my accounting data so I could analyze it programatically
and verify its consistency.

Penny's command line interface and its reports give you
great flexibility to filter and sort postings. Each posting
within a transaction may have its own flags assigned (e.g. to
indicate whether the posting is cleared) and each posting may have
infinite "tags" assigned to it, giving you another way to
categorize your postings. For instance, you might have vacation
related postings in several different accounts, but you can give
them all a "vacation" tag.

You can easily build a program to process downloads of Open
Financial Exchange data from your financial institution. Your
program will merge new transactions into your ledger
automatically.

Full Unicode support.

Penny's reports have color baked in from the beginning. You do not
have to use color, which is handy if you are sending
output to a file or if, well, you just don't like color.

Penny's reports automatically adjust themselves to the width of
your screen. You can easily specify how much or how little data to
see with command line options.

Penny handles multiple commodities (for example, multiple
currencies, stocks and bonds, tracking other assets, etc.) in an
easy and transparent way that is consistent with double-entry
accounting principles. It embraces the philosophy outlined in this
tutorial on multiple commodity accounting:
http://www.mscs.dal.ca/~selinger/accounting/tutorial.html.

Penny stores amounts using only integers. This ensures the
accuracy of your data, as using floating point values to represent
money is a bad idea. Here is one explanation:
http://stackoverflow.com/questions/3730019/why-not-use-double-or-float-to-represent-currency. The
use of integer arithmetic also makes Penny simpler internally, as
there is no need for arbitrary rounding to compensate for the
bizarre and inaccurate results that sometimes arise from the use of
floating-point values to represent currencies.

Freely licensed under the MIT license. If you take this code,
improve it, lock it up and make it proprietary, and sell it,
AWESOME! I haven't lost anything because I still have my code and,
what's more, then maybe I can buy your product and not have to
maintain this one any more!

Tested using QuickCheck. The tests are available in the Git
repository that also contains the main library. Not everything
is tested, but the tests that exist so far have already rooted
out some strange corner-case bugs.

Non-features / disadvantages:

Written in Haskell. Yes, I think Haskell is the best tool ever,
but its compiler is not as commonly installed as compilers for C
or C++, and non-Haskellers will probably find Penny to be more
difficult to install than Ledger, as the latter is written in C++.

Handling commodities requires that you set up multiple accounts;
some might find this cumbersome.

Young and not well tested yet.

Runs only on Unix-like operating systems.

Full Penny functionality is available without a Haskell compiler;
you could even use a pre-compiled binary. However, Penny does not
read configuration files at runtime; instead, to change the
default settings, you will need to have GHC installed so that you
can compile a custom binary.

Can be slow and memory hungry with large data sets. I have a
ledger file with about 28,000 lines. On my least capable machine
(which has an Intel Core 2 Duo at 1.6 GHz) this takes about 1.4
seconds to parse. Not horrible but not instantaneous
either. Generating a report about all these transactions can take
about seven seconds and a little less than 300 MB of memory. I
have eliminated all the obvious slowness from the code and
attempted a rewrite of the parser, which made no difference; other
ideas to speed up Penny with large data sets would involve
substantial changes and this is not at the top of my list because
the program is currently usable with relatively recent hardware.

Unfortunately running "cabal install" will not
install the documentation, so you will need to find the downloaded
archive (usually in
"$HOME.cabalpackageshackage.haskell.orgpenny") and unpack it
to see the documentation. You will want to start by reading the
README file, which will point you to additional documentation and
how to install it if you wish.

Versions that contain at least one odd number are development
versions. They are not posted to Hackage. I try to keep the master
branch in compilable shape. However, development versions may not pass
all tests, and in particular they may have out of date or incomplete
documentation.

Releases consist of code of reasonable quality. All of the groups in
their release numbers are even.

Penny is licensed under the MIT license, see the LICENSE file.

To install the latest release, "cabal install penny" should work. To
also build test executables, run "cabal install -ftest penny". That
will give you two additional executables: penny-test, which when run
will test a bunch of QuickCheck properties, and penny-gibberish, which
prints a random, but valid, ledger file.

To install the manual pages and the documentation, run "sh
install-docs". It will install the manual pages to $PREFIX/share/man
and the other documentation to $PREFIX/share/doc/penny. By default
$PREFIX is /usr/local; you can change this by editing the
install-docs file and changing the "PREFIX" variable.

To remove the manual pages and the documentation, run "sh
install-docs remove."

The first thing you will want to look at is the manual page
penny-basics(7). Then you will want to examine the starter.pny file
in the examples directory, which will show you how to write a ledger
file. penny-suite(7) will then direct you to other documentation that
may interest you.

Though I do use this program to maintain all my financial records, it
is still relatively new and no one but me has tested it. Use at your
own risk.

Dependencies

cabal install will take care of all Haskell dependencies for you;
however, there are also at least two C libraries you will need to
install as Penny depends on other Haskell libraries that use these C
libraries. You will need to make sure you have the "development"
package installed if you use many Linux distributions; a few
distributors, such as Arch, Slackware, and Gentoo, generally don't
ship separate "development" packages so that won't apply to you.
The C libraries are:

curses - on GNU systems this is known as ncurses,
http://www.gnu.org/software/ncurses/ Perhaps other, non-GNU curses
implementations will work as well; I do not know. On Debian
GNU/Linux systems, install libncurses5-dev.